Multipolar cardiac pacemaker lead

Abstract

A multipolar cardiac pacemaker lead wherein the distal end carries a first electrode and at least one sleeve-like additional electrode is provided between the first electrode and the proximal end. Each additional electrode is positively connected with a corresponding helically wound wire-like conductor of the lead by a tubular conductor within an insulating sheath of the lead and by one or more flexible metallic bands each of which has a distal portion soldered or welded to the internal surface of the respective additional electrode, a second portion soldered or welded to the respective tubular conductor, and an S-shaped or Z-shaped intermediate portion extending between and contacting the adjacent convolutions of the respective wire-like conductor. Each tubular conductor is welded or soldered to at least one adjacent convolution of the corresponding wire-like conductor. The wire-like conductors are electrically insulated from each other.

I claim: 
     
       1. A cardiac pacemaker lead having a proximal end and a distal end and comprising a first pacing electrode at said distal end; a second pacing electrode between said first electrode and said proximal end; a first elongated conductor connected to said first electrode and extending toward said proximal end; a second elongated conductor insulated from said first conductor and extending from said second electrode toward said proximal end; at least one substantially band-shaped third conductor; and means for positively connecting said at least one third conductor to said second conductor, said connecting means comprising a tubular fourth conductor positively connected with said at least one third conductor, one of said fourth conductor and said second electrode surrounding the other of said fourth conductor and said second electrode. 
     
     
       2. The lead of claim 1, further comprising a tubular insulator surrounding said first and second conductors and being surrounded by said second electrode. 
     
     
       3. The lead of claim 1, wherein at least one of said first and second conductors is a helically wound wire. 
     
     
       4. The lead of claim 1, wherein said third conductor includes a first elongated portion contacting said second electrode, a second elongated portion contacting said fourth electrode and a substantially Z-shaped or S-shaped intermediate portion between said first and second portions. 
     
     
       5. The lead of claim 4, wherein at least one of said first and second portions extends substantially axially of said second electrode and said fourth conductor. 
     
     
       6. The lead of claim 1, wherein said second electrode has a first length and said tubular fourth conductor has a second length which equals or approximates said first length. 
     
     
       7. The lead of claim 6, further comprising a tubular insulator surrounding said conductors and being surrounded by said second electrode, said second electrode being a press fit on said tubular insulator. 
     
     
       8. The lead of claim 1, wherein each of said first and second conductors is a helically wound wire and said second conductor coaxially surrounds said first conductor, and further comprising a tubular first insulator between (a) said first and second conductors and (b) said second electrode, and a second tubular insulator between said first and second conductors, said fourth conductor being disposed between said second insulator and said second conductor, said at least one third conductor having a first portion connected with an internal surface of said second electrode, a second portion contacting said fourth conductor and an intermediate portion contacting said second conductor and extending substantially transversely of and through said second conductor and said first insulator. 
     
     
       9. The lead of claim 8, wherein said second conductor comprises a plurality of neighboring convolutions and the intermediate portion of said at least one third conductor contacts at least two of said convolutions. 
     
     
       10. The lead of claim 9, wherein said first and second conductors are helically wound wires with convolutions which are electrically insulated from each other and have a common axis and at least substantially identical outer diameters, said fourth conductor being confined in said first and second conductors. 
     
     
       11. The lead of claim 10, wherein said at least one third conductor is electrically connected to an external surface of said fourth conductor and includes a portion disposed between said convolutions. 
     
     
       12. The lead of claim 10, further comprising a tubular insulator between said fourth conductor and said helically wound wires, said second conductor having an end portion extending through an opening of said tubular insulator and connected with said fourth conductor, said at least one third conductor having a first portion connected to said second electrode, a second portion connected to an external surface of said fourth conductor and an intermediate portion extending between said first and second portions through said insulator and between said convolutions. 
     
     
       13. The lead of claim 12, wherein said first portion is connected to an internal surface of said second electrode. 
     
     
       14. The lead of claim 1, wherein said connecting means comprises at least one welded or soldered joint. 
     
     
       15. The lead of claim 1, wherein said second electrode has a first end and a second end between said first end and said first electrode, said connecting means comprising a welded or soldered joint connecting said second end with said at least one third conductor. 
     
     
       16. The lead of claim 1, further comprising a tubular third electrode adjacent said second electrode, a further conductor extending from said third electrode toward said proximal end, and means for electrically connecting said further conductor with said third electrode. 
     
     
       17. The lead of claim 16, wherein said means for electrically connecting said further conductor with said third electrode comprises a tubular conductor surrounded by said third electrode and connected with said further conductor and at least one substantially band-like conductor connecting said third electrode with said tubular conductor. 
     
     
       18. A cardiac pacemaker lead having a proximal end and a distal end and comprising a first pacing electrode at said distal end; a second pacing electrode between said fist electrode and said proximal end; a first elongated conductor connected to said first electrode and extending toward said proximal end; a second elongated conductor insulated from said first conductor and extending from said second electrode toward said proximal end, each of said first and second conductors constituting a helically wound wire with convolutions having common axes and at least substantially identical outer diameters; at least one substantially band-shaped third conductor; means for positively connecting said at least one third conductor to said second electrode nd to said second conductor, including a tubular fourth conductor surrounding said wires and being surrounded by said second electrode; a first tubular insulator surrounding said wires and surrounded by said fourth conductor; and a second tubular insulator disposed between said second conductor having an end portion extending through said first insulator and connected to an external surface of said fourth conductor, said at least one third conductor being connected to said external surface and extending through said second insulator. 
     
     
       19. The lead of claim 18, wherein said second electrode has an internal surface which is connected with said at least one third conductor. 
     
     
       20. A cardiac pacemaker lead having a proximal end and a distal end and comprising a first pacing electrode at said distal end; a second pacing electrode between said first electrode and said proximal end; a first elongated conductor connected to said first electrode and extending toward said proximal end; a second elongated conductor insulated from said first conductor and extending from said second electrode toward said proximal end; at least one substantially band-shaped third conductor; and means for positively connecting said at least one third conductor to said second electrode and to said second conductor, including a tubular fourth conductor surrounded by said second electrode and electrically connected with said second conductor and at lest one welded or soldered joint connecting said at least one third conductor with said fourth conductor. 
     
     
       21. A cardiac pacemaker lead having a proximal end and a distal end and comprising a first pacing electrode at said distal end; a second pacing electrode between said first electrode and said proximal end; a first elongated conductor connected to said first electrode and extending toward said proximal end; a second elongated conductor insulted from said first conductor and extending from said second electrode toward said proximal end; at least one substantially band-shaped third conductor; and means for positively connecting said at least one third conductor to said second electrode and to said second conductor, including a tubular fourth conductor surrounded by said second electrode and connected with said at least one third conductor, said second conductor having an end portion which is welded or soldered to said fourth conductor.